Browsing by Subject "IPM"

Now showing 1 - 6 of 6
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    Brown Marmorated Stink Bug Feeding and Potential for Biological Control in Minnesota Apple Orchards
    (2019-08) Shanovich, Hailey
    There are many serious pests of apple crops in the United States (US), making production challenging for growers. A recent invasive insect in the US, the brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), has emerged as a serious pest of orchard crops with the highest economic losses to date occurring in the Mid-Atlantic region. Populations of H. halys are known to be increasing and spreading throughout the Midwest. If they continue to grow, the insect has potential to become a significant apple pest in the region. My research examined two areas to improve management of H. halys in the Midwest. First, I compared three popular cold-hardy cultivars for risk of injury from H. halys in two-year field and laboratory experiments. Both field and laboratory experiments showed that the cultivars significantly varied in their risk for H. halys injury. One apple cultivar demonstrated a high risk for H. halys injury throughout all experiments and another seemed to be at risk at a later maturity date. Secondly, I characterized the predator community of Minnesota apple orchards through season-long sampling over two years. The relative abundances and composition of the predators in orchards differed from previous studies in both proximate and distant states, which has direct implications for the level of biological control that can be achieved for H. halys in Minnesota. In addition, I compared the abundances of total predators and specific predator groups between apple cultivars sampled and found there to be significant differences across years. Lastly, I examined the impact of natural enemies on H. halys in Minnesota apple orchards by conducting sentinel egg mass studies over two years. Overall predation was found to be low with no parasitism observed. This finding indicates that with current standard management practices in conventional Minnesota apple orchards, control of H. halys is likely to be low by existing natural enemies. The results from my thesis will provide information to fine tune IPM plans for H. halys to help create a more sustainable apple production system for growers in the Midwestern US.
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    Evaluating Host Plant use by Spotted Wing Drosophila, Drosophila suzukii, in Minnesota.
    (2017-05) Sward, Grace
    Spotted wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), is newly established in North America and become one of the most devastating pests for small fruit crops. With a broad host range, thin-skinned berries are particularly susceptible to infestation, and fruit producers are desperate for methods to control this pest. One of the keys to developing an integrated management program for SWD is to understand host preference, varietal susceptibility of crop hosts, and overall susceptibility and use of non-crop hosts. In this thesis, the infestations levels and host plant growth stages were recorded over time during growing seasons of one day in 2014, and various sampling dates in 2015 and 2016 in Minnesota. Both crop and non-crop host plants were examined for their phenological and overall susceptibility. The first research chapter was performed working in replicated small plots, experiments were conducted to evaluate differences in varietal susceptibility on cold hardy red primocane fruiting raspberries. Significant differences were observed in both the level of infestation and in the average number of larvae per berry by variety. In addition, it appears that there is a significant negative correlation between the level of infestation and the number of larvae per fruit with the time of sampling, but only an interaction of variety and time for the number of larvae per berry. The second research chapter was performed using nine field sites of either farm or non-farm wild locations separated by a minimum of 400 meters. Crop hosts: raspberry, blueberry, and elderberry, as well as non-crop host plants were examined and sampled for fruit ripening stages an infestation rates. Significant differences were observed in infestations within non-crop host plants and crop host plants. Crop hosts sustained infestations starting in the green phenological stage. These data provide a better understanding of the biology and ecology of this pest which is critical in refining current management practices. Knowledge of these interactions can aid in optimizing control strategies such as fine-tuning spatial and temporal control measures, which may be particularly important for early season infestations.
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    Hazelnut and adult hazelnut weevil monitoring at Minnesota sites from 2020-2022
    (2023-07-14) Shanovich, Hailey N; Anderson, Pheylan A; Aukema, Brian H; hnshanovich@gmail.com; Shanovich, Hailey N
    This data was collected in order to determine the phenology of adult hazelnut weevils (Curculio obtusus) within interspecific hybrid hazelnut (Corylus americana x Corylus avellana) plantings in Minnesota and identify hazelnut factors that might be driving the weevils within-field abundance and infestation/damage in the crop between different hazelnut genotypes. Adult hazelnut weevil lay eggs into developing hazelnuts and their larvae then develop inside hazelnuts, devouring the edible kernel, directly impacting crop yield. Therefore, the objective was to determine when this behavior occurs in the Minnesota crop and to identify any plant-level or nut-level factors driving spatial trends in their abundance and nut infestation within the hazelnut plantings.
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    Insecticide Resistance Management For Aphis glycines (Hemiptera: Aphididae): Understanding The Biological Mechanisms And Farmer Practices
    (2023-08) Lozano, Rosa
    Soybean aphid (Aphis glycines Matsumura) (Hemiptera: Aphididae) is a pest that can severely impact soybean crops in the United States. Over the years, the repeated and widespread use of pyrethroid insecticides has led to the selection of resistant individuals within soybean aphid populations. The two insecticide resistance mechanisms documented in soybean aphids are metabolic detoxification and target site alteration. Farmers are key in implementing integrated pest management (IPM) and insecticide resistance management (IRM) strategies to manage soybean aphids. Resistance mechanisms are constantly evolving, insecticide resistance is becoming a barrier to soybean aphid control, and current farmer management approaches are unknown. My dissertation is focused on understanding the variability of resistance mechanisms and farmers practices to help inform IPM and IRM.
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    IPM (Integrated Pest Management) of Midwest Landscapes
    (Minnesota Agricultural Experiment Station (MAES), 2004) Krischik, Vera A.; Davidson, John
    These pest and beneficial insect profiles and IPM information are from a 2004 manual published by the MAES (University of Minnesota Agricultural Experiment Station) in cooperation with USDA NCERA 224/NCR 193, North Central Committee on Landscape IPM.
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    The role of entomopathogenic fungi in the management of Soybean Aphid.
    (2011-07) Koch, Karrie Anne
    Soybean aphid, Aphis glycines Matsumura, is an invasive arthropod pest of soybean which has been present in North America since 2000. Aphid outbreaks cause economic damage via increased insecticide use and reduced yield. Management of this pest has been achieved almost exclusively with foliar applications of broad spectrum insecticides. The purpose of this research is to determine how a fungal pathogen of soybean aphid, Pandora neoaphidis, can contribute to the natural regulation of aphid populations. Pandora neoaphidis is an endemic aphid pathogen and the most frequently reported pathogen infecting soybean aphid. Analysis and field validation of a mathematical model describing the soybean aphid-P. neoaphidis pathosystem has shown that the fungus can establish and persist when aphid densities are lower than the economic threshold of 250 per plant; thus confirming that P. neoaphidis is capable of contributing to aphid control before aphids reach damaging densities. Additionally, field experiments demonstrate that emerging aphid management tactics including aphid-resistant soybean plants and insecticide seed treatments have minimal impacts on aphid infection rates by P. neoaphidis and are likely compatible with this natural enemy. Cage studies demonstrate that the presence of Harmonia axyridis in soybean aphid colonies also harboring P. neoaphidis has no impact on aphid infection by the fungus. Pandora neoaphidis may also be an important regulator of aphid populations on the aphids’ primary host, Rhamnus cathartica, or common buckthorn, as soybean aphid morphs which occur on this host are the most susceptible to infection. However, fungicide applications to soybean can have lasting impacts on the beneficial fungi infecting soybean aphid as foliar fungicide applications to soybean reduced the rate of aphid infection both before and after aphids moved to the primary host in the autumn. In summary, P. neoaphidis is likely an important member of the natural enemy community which provides a significant level of aphid biological control.